A hot runner is utilized to transfer molten material, typically plastic resin, from an injection unit of an injection molding machine to at least one cavity defined in a pair of mold plates. A hot runner typically includes a manifold plate, a manifold housed in the manifold plate, and a backing plate that supports the manifold and manifold plate. The hot runner routes molten material from a central sprue, which connects to an injection unit on an injection molding machine, to a plurality of nozzles which inject the molten material into cavities in the mold. The hot runner divides the flow of molten material into several branches as it flows from the central sprue to the nozzles.
Referring now to FIG. 1, a cross-section of a hot runner 8 is shown. A manifold 10 is located between a manifold plate 12 and a backing plate 14. The manifold 10 has one or more melt channels 18 that communicate the molten material from a sprue 16 connected to the manifold 10 at a central location. The hot runner 8 has nozzles 6 in fluid connection with the manifold 10.
One limitation of this prior art hot runner 8 is that the manifold 10, manifold plate 12, and backing plate 14 must be replaced each time a new hot runner 8 is desired. The possibility of a reusable and reconfigurable manifold 10 (or melt distribution system), manifold plate 12, backing plate 14 represents a significant potential cost and time saving benefit. In addition to these cost and time benefits, lead times for a new hot runner 8 can be considerable and with the present invention significantly reduces lead time.
Therefore, it would be desirable to provide a hot runner 8 that is reusable and reconfigurable. Specifically, it would be very desirable to provide manifolds 10 (or melt distribution systems), manifold plates 12, and backing plates 14 that are reusable and reconfigurable to different drop locations. Further, it would be desirable to have nozzles 6 that are reusable as well.
The present invention is directed to meeting one or more of the above-stated desirable objectives.